Field
This disclosure is generally related to the field of data storage. More specifically, this disclosure is related to a method and system for facilitating data destruction in a phase change memory-based storage device.
Related Art
The proliferation of the Internet and e-commerce continues to create a vast amount of digital content. Various storage systems have been created to access and store such digital content. One such storage system uses phase change memory (PCM), which is a type of non-volatile random access memory. PCM uses a specific type of glass and can hold multiple bits in a single cell (or sector). PCM is faster than NAND flash, and has a higher density than conventional dynamic random access memory (DRAM). PCM has a low read/write latency, and may be used for fast persistent data storage. In contrast with a DRAM Dual In-line Memory Module (DIMM) (which loses its data after a power loss), PCM, as a non-volatile memory, retains its stored data even after a power loss. The data stored in the PCM may include sensitive information, which can be vulnerable to unwanted access after a power loss. One way to protect the data is to overwrite all of the data stored in the PCM. However, because the PCM can have a high density and a high capacity (e.g., 4 terabytes), it is neither feasible nor efficient to overwrite all the physical cells of the PCM. For example, after a power loss, there may be an insufficient amount of residual charge to overwrite all the cells of the PCM. Furthermore, making the stored data permanently unrecoverable after a power loss may not be a desired strategy for managing the system. Thus, while PCM provides benefits including both an access speed greater than NAND flash and a storage capacity greater than DRAM, the issue of efficient data destruction to protect sensitive data after a power loss remains unsolved.